Answer:
b and d
Step-by-step explanation:
just took the test
Answer:

Step-by-step explanation:
In order to add or subtract numbers in scientific notation, the powers of ten must have the same exponent. In this caes the diameter of an average human body cell is a power of -4 and the diameter of a plant cell is a power of -3. In order to add them, we can move the decimal over for the body cell diameter:

Add the two values: 
Answer:
Step-by-step explanation:

Answer:
$230
Step-by-step explanation:
Answer:
x=5 ; Area= 84m²
Step-by-step explanation:
(x+2)²+(4x+2)²=(5x)²
x²+4+4x+16x²+16+32x=25x²
8x²-36x-20x=0
x=5;x=-1
hypotenuse should be positive
x=5
area=lxb/2