Let p1 = 2, p2 = 3, . . be the list of primes, in increasing order. consider products of the form (p1 × p2 × ·· ·× pn) + 1 (compare with the proof of corollary 1.3.4). show that this number is prime for n = 1, . . , 5. show that when n = 6 this number is not prime. [use your answer to exercise 1.3.1. a calculator will speed the work of checking divisibility.]

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

When using the ohmmeter function of a digital multimeter, the leads are placed in what position relative to the component being tested? a. parallel b. control c. series d. line