# HSF-BF.A.1

Write a function that describes a relationship between two quantities.

**a**
Determine an explicit expression, a recursive process, or steps for calculation from a context.

**b**
Combine standard function types using arithmetic operations. For example, build a function that models the temperature of a cooling body by adding a constant function to a decaying exponential, and relate these functions to the model.

**c**
Compose functions. For example, if $T(y)$ is the temperature in the atmosphere as a function of height, and $h(t)$ is the height of a weather balloon as a function of time, then $T(h(t))$ is the temperature at the location of the weather balloon as a function of time.

## Tasks

Summer Intern

Skeleton Tower

Susita's Account

A Sum of Functions

Crude Oil and Gas Mileage

Kimi and Jordan

Temperature Conversions

The Canoe Trip, Variation 1

The Canoe Trip, Variation 2

Lake Algae

Compounding with a 5% Interest Rate

Compounding with a 100% Interest Rate

Graphs of Compositions

Flu on Campus

Building an Explicit Quadratic Function by Composition

1,000 is half of 2,000