89% I.e C should be the answer I hope it helps you . it should be
4+5=9
4÷9×200=88.8% approximately 89%
Answer: 
Step-by-step explanation:
The surface area of a rectangle can be calculated with:

The surface area of a trapezoid can be calculated with:

Calculate the area of the base, wich is a rectangle:

There are two equal rectangles, therefore, multiply the area of any of them by 2:

Calculate the area of the other rectangle:

There are two equal trapezoids, therefore, multiply the area of any of them by 2:

Therefore, the surface area will be the sum of all the areas calculated:

(-2a^5b^4) * (42ab^6) = -84a^6b^10