The fastest single lap of the Indianapolis 500 car race was 38.1 seconds. If the race track is 4.0 km long, what was the average speed of Eddie Cheever, Jr, who accomplished this feat?

Could someone . i have tried to solve myself but my calculation is off

(a) calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 10.0 g. silver has 47 electrons per atom, and its molar mass is 107.87 g/mol. (b) imagine adding electrons to the pin until the negative charge has the very large value 1.00 mc. how many electrons are added for every 109 electrons already present

The frequencies refer to the sample data collected from a population of interest when performing a hypothesis test comparing two or more population proportions.