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What is the significance of performing mouth-to-mouth breaths during CPR?

Exhaled air contains a higher percentage of CO2 than inhaled air, due to it being a waste product of respiration. By breathing excess CO2 into the patient, the blood acidity will decrease and will be dete...

Answered by Phoebe D. • Biology tutor

2934 Views

'The lives of the Russian peasants were transformed in the years 1928 to 1964.' Assess the validity of this view

The years 1928-1964 were a time in which Russia as a nation, faced a total transformation. From changes in economic and political structure, to a complete shift in social order, most aspects of an average...

Answered by Jasmine B. • History tutor

4450 Views

Express 4sin(x)+6cos(x) in terms of Rsin(x+a) where R and a are constants to be determined (a should be given in rad).

R=sqrt(42)=6.48...a=arcos(4/sqrt(42))=0.905...Rsin(x+a)=6.48sin(x+0.905)

Answered by Benjamin U. • Maths tutor

4276 Views

Integrate ln(x)

Take ln(x) = 1 * ln(x) and integrate by parts. Let u = ln(x) and dv/dx = 1 such that du/dx = 1/x and v = x. Using the integrating by parts formula, you get x ln(x) - integral(1) = x ln(x) - x + c.

Answered by Jason Y. • Maths tutor

3908 Views

A ball of mass m moves towards a ball of mass km with speed u. The coefficient of restitution is 0. What is the final velocity if the first ball after the collision.

Coefficient of restitution is defined as the ratio of the relative speed of separation of the balls to the relative speed of approach. A ratio of 0 means that the speed of separation has a value of zero a...

Answered by Susannah E. • Maths tutor

3236 Views