Answer:
900
Step-by-step explanation:
multiply 2x2x3x3x5x5
4x9x25 which is 900
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:
The formula for the nth term of this sequence is: 31 + (n-1)X6
Step-by-step explanation:
This is an arithmetic sequence (ie. each term is the last term with a fixed value added to it).
T1 =31
T2 = 37 = T1 + 6 = 31 + 6
T3 = 43 = T2 + 6 = 31 + 6 + 6 = 31 + 6X2
…
In general, the nth term is 31 + 6(n-1)
Yes it is a geometric sequence and the common ratio is 2/3