Anton van Leeuwenhoek, a $17^{\text {th }}$-century pioneer in the use of the microscope, described the microorganisms he saw as "animalcules" whose length was " 25 thousandths of an inch." How long were the animalcules in meters?

Define conversion feature; a call feature. What are stock purchase warrants?

Without a calculator, decide whether the quantities are positive or negative.

$$-4^3$$

The SI unit of electric potential difference is the (a) joule, (b) newton per coulomb, (c) newton-meter, (d) joule per coulomb.

Write the equality and conversion factors for the following pair of unit: dimes and dollars.

Without a calculator, decide whether the quantities are positive or negative.

$$(-3)^4$$

The Cobalt $({}_{27}^{57}\mathrm{Co})$ emits 122-keV gamma rays. If a 70-kg person swallowed 2.0 $\mu$Ci of ${}_{27}^{57}\mathrm{Co}$, what would be the dose rate (rad/day) averaged over the whole body? Assume that $50$ percent of the $\gamma$-ray energy is deposited in the body. $\it{[Hint:}$ Determine the rate of energy deposited in the body and use the definition of the rad.$]$

Let $(a, b)=1$. Prove that $\left(a, b^n\right)=1$ for all positive integers $n$.

Find the probability $P(1 \leq Z \leq 2)$ for a standard normal random variable Z.

Determine the cumulative distribution function of a binomial random variable with n=3 and p=1/4.

Two balls are connected by a $150-\mathrm{cm}$-long massless rod. The center of mass is $35 \mathrm{~cm}$ from a $75 \mathrm{~g}$ ball on one end. What is the mass attached to the other end?

A pizza restaurant features ten different kinds of toppings. When you order a quadruple pie, you get to pick four toppings on your pizza. a. How many different quadruple pizzas can be made if the four toppings must be different? b. How many different quadruple pizzas can be made if toppings may be repeated (e.g. onions, olives, and double mushrooms, or triple anchovies and garlic).

What is the conversion factor when converting from liters to milliliters?

A $4.00-\mathrm{kg}$ object is attached to a vertical rod by two strings, as in Figure . The object rotates in a horizontal circle at constant speed $6.00 \mathrm{~m} / \mathrm{s}$. Find the tension in (a) the upper string and (b) the lower string.