I NEED THE WORKING AND THE EXPLANATION FOR QUESTION NO.3 ONLY

Progressions 1. Find the sum of the following progressions: (a) 1.00, 1.04, 1.08,..., 2.12, 2.16. (b) 1, 3, 9, ..., 243, 729. 2. (a) How many terms of the progression 50, 46, 42, ... must be taken for the sum to be equal to 96? (b) If the common ratio of a G.P. is 4 and the ninth term is 131,072, find the sum of the first six terms of the G.P. 3. The management of Sunflower Carriage Lid is planning to run down production and sales of two of its existing products, A and B. Sales of A in the month just ended were 8,400 units. It is planned to reduce sales by 600 units per month. Sales of B in the month just ended were 6,000 units. It is planned to reduce sales by one fifth each month. How many more units of A and B will be sold before production and sales cease entirely