Answer:
Step-by-step explanation:
Sum: 6 * 10^-4 + 1.5*10^-4 = 7.5 * 10^-4
Difference: 6 * 10^-4 - 1.5 * 10^-4 = 4.5 * 10^-4
Product: 6*10^-4 * 1.5 * 10^-4 = 9 * 10^-8
Quotient: 6*10^-4/1.5 * 10^-4 = 4
Notice the answers, because they give you the rules.
When adding exponents and rationales, if the powers are the same then the rationales merely add.
Same rule applies to subtraction. Retain the powers and subtract the rationales.
When multiplying the rationales multiply, but the rationales add. they don't stay the same.
When dividing, the rationales divide and the powers subtract -- numerator minus denominator
