Bella is an electrician.

She charges $150 to attend a job and then a fixed price for each minute she spends on the job.

The graph below shows Bella's charge based on the number of minutes she spends at the job.
 

 
How much will Bella charge for a job that takes 60 minutes?

David has a job selling mobile phone plans. His weekly salary, dollars, is calculated using the rule below:

where is the total value in dollars of the mobile phone plans he sells that week.

David sold $32 000 worth of mobile phone plans in a given week.

What was David's salary in the week?

On a weekend, Abbey works 8 hours at her normal pay rate and 12 hours at time and a half of her normal pay.

Abbey was paid $707.20 in total for this work.

What is her normal pay rate per hour?

Olivia earned $17.24 per hour working at a pizza store.

This week she worked for   hours.

She used the money she earned this week to buy concert tickets for herself and her friends.

Each concert ticket cost $14.15.

What is the maximum number of concert tickets Olivia could have bought?