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NinjaDevo that heading was just to make the actual (so hard) question look attractive!lol!

Maybe it is locate basic information. - don't know.

Mari and Dragonslayer,

You need to explain the steps - the answer by itself is of little or no educational value.  

(6+4)^2+(9/3-1)

=10^2 + (3-1)

=100+2

=102

NOW what are the rules for order of operation:

Remember PEDMAS

1) Paretheses 

2) exponents

3) division and multiplication - equally important do them from left to right.

4) addition and subtraction - equally important do them from left to right.

Thnak You Alan for the answer! I understand now the method! Not certain though about the amount of seconds in one degree. I think is 3600 not 360 ? Plz correct me if I am wrong. Once again, thank You for the answer!

That wasn't me. Not sure if that is the troll or serious post. I'm logged in when I post or state otherwise. 

Yes it does thank you. Can you also assist with the question: a 2kg block is projected up a plane of angle 30 degrees with the horizontal. V₀ is 5m/s and μ = 0. Find the distance the lock travels along the incline. 

Please explain process of forces acting on it, as you did in the last post @Alan. I want to see how to reason logically and understand the process. Thanks.

Zegroes, you need to learn what is in a pack of cards.

school probablility is often done using cards and students are expected to know what a pack of playing cards consists of.  Learn now and it is one less thing  that will trip you up later on!

If you are referring to the friction coefficient question then yes. g = 9.81m/s²

You probably mean "degrees" not "degrades", in which case, one way is to enter 179+50/60+14/3600 - (119+58/60+41/3600) to get the answer in degrees, remembering that there are 60 minutes in a degree and 3600 seconds in a degree.  *Edited to correct number of seconds in degree!

$${\mathtt{179}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{50}}}{{\mathtt{60}}}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{14}}}{{\mathtt{3\,600}}}}{\mathtt{\,-\,}}\left({\mathtt{119}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{58}}}{{\mathtt{60}}}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{41}}}{{\mathtt{3\,600}}}}\right) = {\mathtt{59.859\: \!166\: \!666\: \!666\: \!666\: \!7}}$$

This gives 59° plus a bit.  Turn the extra into minutes by multiplying by 60:

$${\mathtt{0.859}}{\mathtt{\,\times\,}}{\mathtt{60}} = {\frac{{\mathtt{2\,577}}}{{\mathtt{50}}}} = {\mathtt{51.54}}$$

This is 51' plus a bit.  Turn the extra into seconds by multiplying by another 60.

$${\mathtt{0.54}}{\mathtt{\,\times\,}}{\mathtt{60}} = {\frac{{\mathtt{162}}}{{\mathtt{5}}}} = {\mathtt{32.4}}$$

This is 32'' to the nearest second.

So the overall result is 59°51'32''

The first equation, which should probably be written as 1/2*m*v₀² = F_fr*D, says that the initial kinetic energy is equal to the work done by friction in bringing the object to rest (the right-hand side is frictional force*distance which is work, which is a form of energy transfer).

The frictional force is usually represented by F_fr = μ*F_n, where F_n is the normal force; that is, the force holding the object on the floor, namely, its weight (so F_n = m*g, where m is the object's mass and g is the acceleration of gravity).   μ is called the coefficient of friction.

So, putting this together, we end up with: 1/2*m*v₀² = μ*m*g*D which can be rearranged to find μ = (1/2*m*v₀²)/(m*g*D) and the m cancels so μ = (1/2*v₀²)/(g*D).

Does this make it clearer?