Ranze, the Store Manager of SM Bacoor Supermarket wants to determine the effect of TV advertising to the branch sales per month. He was able to monitor the TV Ads expenditure and the sales per month. This year, the TV Ad expenditure and sales respectively are as follows: January is P 18,000 and P 125,000 February is P 15,000 and P 126,000 March is P 23,000 and P 125,000 April is P 19,000 and P 135,000 May is P 16,000 and P 128,000 June is P 26,000 and P 133,000 July is P 20,000 and P 127,000 August is P 25,000 and P 138,000 September is P 21,000 and P 126,000 October is P 24,000 and P 131,000 November is P 22,000 and P 136,000 December is P 17,000 and P 135,000 

REQUIRED: 

1. What is the monthly sales forecast if there is no TV Ad expenditures? 

2. What is the sales forecast if the TV Ad expenditure starts at P 25,500?

3. What is the sales forecast if the TV ads at #2 will increase at P 2,000 interval from P 25,500 until it reaches P 59,500?