Which exponential expression is equivalent to (4x^2 y^3)^2

Two customers went to a post office. first customer paid $12 for 14 and 5 envelopes the second paid 24.80 for 10 postcards and 15 envelopes. what is cost of each envelope?

The average length of a king cobra is 3.7 m. the record length is 1.88 m longer than the average. how long is the record holder?

The measures of the angles in △abc are given by the expressions in the table. angle measure angle a 65° angle b (3x−10)° angle c (2x)∘ find the value of x. then find the m∠b and m∠c.