Please help, Thank YOU if you try.

If { an} is an arithmetic sequence, a₁ = 1, and a₁₀₀ = 625, evaluate ${1}/(\sqrt{a_1}+\sqrt{a_2}) + 1/(\sqrt{a_3}+\sqrt{a_4}) + ... + 1/(\sqrt{a_{99}}+\sqrt{a_{100}})?$