I need help with number 2

Aresearch company wants to test the claim that a new multivitamin to improve short term memory. state the objective of the experiment, suggest a population, determine the experimental and control groups, and describe a sample procedure.

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles. i'm desperate.

What is the order of operations for 2 + (3 - 9) ÷ -3 · 4 in number order 1. subtraction 2. division 3. addition 4. multiplication