Explanation:
4. Let's multiply the coefficients. 2 * 6 * (-5) = -60. As for the exponents, since they have the same base we'll just add the exponents giving us s^(2 + 1 + 4) = s^7 so the answer is -60s^7.
7. -2/3 * -1/2 * -4 = -4/3 and the exponent is b^(2 + 3 + 4) = b^9 so the answer is -4/3b^9