Answer:
C.
Step-by-step explanation:
At least means greater than or equal to.
Answer: No solutions
Step-by-step explanation: If you solve the problem all the way, you get 0 = 4 which is not valid so there is simply no solution
B. 188-80=108
The closest answer there is 100
Answer: 
Step-by-step explanation: In some cases you must apply the exponent rule, simplify, or multiply them together to get your answer.