Hello can someone help me please ​

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

The volume of a sphere is increased by 6%. calculate the corresponding percentage increased in it area.

At the "no mutants allowed" country farm, every sheep has 4 legs, every chicken has two legs, and all animals have only 1 head. asked to count how many sheep and chicken are in the fields, a farm boy reports back that there are 140 feet and 50 heads. how many sheep and chicken are there? there are sheep and chicken at the farm.