Rauhan

1360

17500

IKR

are u referring to y=mx+c?

Trust me bro i feel ya cuz i have my maths final on Sunday

There are 365 days in a year and in one day there are 24 hours so u do 

365*24=8760 hrs

First lets take an example like 5^-2 

to remove the minus u do 1/5² 

and the same for 0.4^-2 

u do 1/0.4 ²

Just use the calculator on the home page 

Anyways the answer is 

99/80=1.2375

You can use the Cosine rule which is

CosA= c² + b2- a²/ 2bc 

and the same with B and C

It's something like

https://www.desmos.com/calculator/anyb1qonol