Add the complex number :(4+8i) + (-2-1). A. 2+9i B. 2+ 7i C. 6+ 9i D. 6+ 7i

7just use a calculator lmdo

Volume is length times width times height so
20 times 8 times 30 which is 4,800
surface area is ph (p is perimeter of base), h is height.
so perimeter would be length+length+width+width so 20+20+8+8 which is 56. so multiply 56 times 30 which is 1680. hope this !