2. (15 marks) A web-based movie site offers both standard content (older movies) and premium content (new releases, 4K, and even some 8K material). The site offers two types of membership plans. Plan 1 costs $4/month and allows up to 50 hours of standard content per month and up to 10 hours of premium content per month. Extra hours under Plan 1 can be purchased for $0.40 hour for standard content, and $0.80 per hour for premium content. Plan 2 costs $20/month and allows unlimited viewing of both standard and premium content. (a) Write an expression for the monthly cost of watching a hours of standard con- tent and 19 hours of premium content using Plan 1. (b) For what values of a and b is Plan 1 cheaper than Plan 2? (c) Show the region found in part (b)