91Ó°ÊÓ

The speed limit in Canada is \(100 \mathrm{~km} / \mathrm{h}\). (a) How many miles per hour is this? (b) How many meters per second?

The muzzle velocity of a projectile fired from a \(9 \mathrm{~mm}\) handgun is \(1200 \mathrm{ft} / \mathrm{s}\). (a) How many miles per hour is this? (b) How many meters per second?

The white blood cell concentration in normal blood is approximately 12,000 cells \(/ \mathrm{mm}^{3}\) of blood. How many white blood cells does a normal adult with \(5 \mathrm{~L}\) of blood have? Express the answer in scientific notation.

Calculate the specific heat of copper if it takes \(96 \mathrm{~J}\) to heat a \(5.0 \mathrm{~g}\) sample from \(25^{\circ} \mathrm{C}\) to \(75^{\circ} \mathrm{C}\).

A white solid with a melting point of \(730^{\circ} \mathrm{C}\) is melted. When electricity is passed through the resultant liquid, a brown gas and a molten metal are produced. Neither the metal nor the gas can be broken down into anything simpler by chemical means. Classify each-the white solid, the molten metal, and the brown gas - as a mixture, a compound, or an element.

Drug dosages are typically prescribed in units of milligrams per kilogram of body weight. A new drug has a recommended dosage of \(9 \mathrm{mg} / \mathrm{kg}\). (a) How many milligrams would a \(55 \mathrm{~kg}\) woman have to take to obtain this dosage? (b) How many \(125 \mathrm{mg}\) tablets should a \(18 \mathrm{~kg}\) child take to receive the recommended dosage?

Chloral hydrate, a sedative and sleep-inducing drug, is available as a solution labeled \(10.0 \mathrm{gr} /\) fluidram. What volume in milliliters should be administered to a patient who is meant to receive 7.5 gr per dose? \((1 \mathrm{gr}=64.8 \mathrm{mg} ; 1 \mathrm{fluidram}=3.72 \mathrm{~mL})\)

Imagine that you place a piece of cork measuring \(1.30 \mathrm{~cm} \times 5.50 \mathrm{~cm} \times 3.00 \mathrm{~cm}\) in a pan of water and that on top of the cork you place a small cube of lead measuring \(1.15 \mathrm{~cm}\) on each edge. The density of cork is \(0.235 \mathrm{~g} / \mathrm{cm}^{3}\) and the density of lead is \(11.35 \mathrm{~g} / \mathrm{cm}^{3}\). Will the combination of cork plus lead float or sink?