Question

The mass of a dust particle is approximately 7.5×10−10%0D%0A7.5%0D%0A×%0D%0A10%0D%0A−%0D%0A10%0D%0A kilograms and the mass of an electron is 9.1×10−31%0D%0A9.1%0D%0A×%0D%0A10%0D%0A−%0D%0A31%0D%0A kilograms. Which expression would you use to find out how many electrons you need to equal the mass of one dust particle?(1 point)%0D%0AResponses%0D%0A%0D%0A(9.1×10−31)(7.5×10−10)%0D%0A(%0D%0A9.1%0D%0A×%0D%0A10%0D%0A−%0D%0A31%0D%0A)%0D%0A(%0D%0A7.5%0D%0A×%0D%0A10%0D%0A−%0D%0A10%0D%0A)%0D%0Aopen paren 9 point 1 times 10 to the negative 31 power close paren times open paren 7 point 5 times 10 to the negative 10 power close paren%0D%0A%0D%0A(7.5×10−10)(9.1×10−31)%0D%0A(%0D%0A7.5%0D%0A×%0D%0A10%0D%0A−%0D%0A10%0D%0A)%0D%0A(%0D%0A9.1%0D%0A×%0D%0A10%0D%0A−%0D%0A31%0D%0A)%0D%0Aopen paren 7 point 5 times 10 to the negative 10 power close paren times open paren 9 point 1 times 10 to the negative 31 power close paren%0D%0A%0D%0A(7.5×10−10)÷(9.1×10−31)%0D%0A(%0D%0A7.5%0D%0A×%0D%0A10%0D%0A−%0D%0A10%0D%0A)%0D%0A÷%0D%0A(%0D%0A9.1%0D%0A×%0D%0A10%0D%0A−%0D%0A31%0D%0A)%0D%0Aopen paren 7 point 5 times 10 to the negative 10 power close paren divided by open paren 9 point 1 times 10 to the negative 31 power close paren%0D%0A%0D%0A(9.1×10−31)−(7.5×10−10)%0D%0A(%0D%0A9.1%0D%0A×%0D%0A10%0D%0A−%0D%0A31%0D%0A)%0D%0A−%0D%0A(%0D%0A7.5%0D%0A×%0D%0A10%0D%0A−%0D%0A10%0D%0A)%0D%0Aopen paren 9 point 1 times 10 to the negative 31 power close paren minus open paren 7 point 5 times 10 to the negative 10 power close paren%0D%0A%0D%0A(9.1×10−31)÷(7.5×10−10)

Answer 1

(7.5×10−10)÷(9.1×10−31)
(open paren 7.5 times 10 to the negative 10 power close paren divided by open paren 9.1 times 10 to the negative 31 power close paren)