Gabriella weighs 450 n. she climbs a flight of stairs to a height of 3 m. it takes her 5 seconds. how much work does gabriella do when she climbs the stairs?

a.
150 j

b.
270 j

c.
1350 j

d.
2250 j

What happened to the amount of carbon dioxide in the atmosphere from 2010–2017?

The fact that the total amount of energy in a system remains constant is a(n)

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)