Austin and his friends are pushing a heavy box up a ramp. How can
they increase the rate at which the box is moving?
Select one
Increase the angle of the ramp.
Increase the friction of the ramp.
Increase the force they are using to move the box by adding more helpers.
o oo
Decrease the force they are using to move the box.

Liv sheldon given the balanced equation for an organic reaction: c2h2 + 2cl2 → c2h2cl4 this reaction is best classified as *

The formation of a solid, also known as a is an indication of a chemical change. precipitate particulate particle powder

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)