Answer:
B. 30
Step-by-step explanation:
2m^2 + 12
m = 3
2(3)^2 + 12
3 squared is 9
2(9) + 12
2 times 9 is 18
18 + 12 = 30
2m^2 + 12 = 30
So we subtitute 3 to any "m" in your problem so,
2m^2+12
2(3)^2+12
2(9)+12
18+12
30
So, B is the correct answer!