plsssssssss help I really need to do this I will give brainliest to anyone who solves

Answer:
MSP: 6a/2
CUB: ab/2
ABC: 20 square centimeters
KDR: 5x cm * 3x cm / 2
Step-by-step explanation:
MSP: 6 x a divided by 2
CUB: a x b divided by 2
ABC: 8 x 5 divided by 2
KDR: 5xcm * 3xcm divided by 2