1) atom a has an atomic number of 19 and mass number of 40. atom b has an atomic number of 20 and a mass number of 40. which of these is an accurate statement? a) atom a has more protons than atom b. b) atom a has one less proton and one more neutron than atom b. c) atom a has an extra nucleon compared to atom b. d) atom a has one more proton and one more electron than atom b.

Select all the correct answers. which three statements about electromagnetic radiation are true?

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.

Which of the following could represent a single-replacement reaction? a. element + compound = element + compound b. element + element = compound c. compound +compound = compound + compound d. compound = element + element