6. Following data reveals the sales of a company due to the number of sales persons and the years of experience. By using the multiple regressions, estimate the sales of the company using two salespersons with experience of nine years, Sales(Rs'000) 20 30 25 20 40 60 15 No. of sales person 2 3 S 4 2 1 4 5 7 years of experience 11 10 8 7 7. 8

Apiping systems consists of 6 m of 6-std type k and 12 m of 4-std type k, both drawn copper tubing. the system conveys ethylene glycol at a rate of 0.013 m3/s. the pressure drop across the system is to be calculated. there are two 90° elbows in the 6-in pipe, a reduction from the 6-in pipe to the 4-in pipe and four 90° elbows in the 4-in pipe. all fittings are soldered (same as flanged) and regular. the inlet and outlet of the system are at the same height.