The answer to this is the second choice
Hello! So the formula for compound interest is P(1 + r)^t, where r = rate, P = principal, and t = time (years). C is out, because you multiply the rate and principal together to get the price, not add. You raise the decimal to a certain power, based on the amount of years. You add 1 to the rate. 5% in decimal form is 0.05 and you must add 1 to the amount, which eliminated B. The only answer that works is A, because it shows the correct formula. The answer is A.
A greatest common factor is the largest number that goes into two or more numbers (in this case two). To find the GCF of two numbers, we have to find the prime factorization (how to express a number as a product of prime numbers) and then see which numbers are common in both of the prime factorizations.
13. The prime factorization of 8 is 2 * 2 * 2. The prime factorization of 26 is 2 * 13. Looking at the prime factorizations, we can see that both of them have 2. That means that the GCF is 1 * 2 which is 2.
12. The prime factorization of 105 is 3 * 5 * 7. The prime factorization of -30 is -5 * 6. We see that the number shared 5. That means that the GCF is 5 * 1 or 5.
