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How does a vaccine lead to the production of antibodies against a virus?

The vaccine contains antigens of the virus. When injected, these antigens are recognised by macrophages which engulf the antigen and present the antigens on their surface. Once the antigens are presented,...

Answered by Keziah A. • Biology tutor

2270 Views

How should I use incorporate secondary, critical quotations into my own responses to literature?

It's important to approach the critics with a critical attitude. This means applying to the secondary material the same rigour and attention which you give to the primary material. You can do this in a fe...

Answered by William B. • English tutor

1340 Views

Find the exact value of the integral of (2+7/x), between x=1 and x=e. Give your answer in terms of e.

1.) Find the integral of each term. --> [2x +7ln(x)]. --> Uses standard integrals--> e.g. that the integral of 1/x is ln(x).
2.) substitute values into the integral. --> [2(e)+ 7ln(e)]-...

Answered by • Maths tutor

3418 Views

Prove by induction that 1^2 + 2^2 + 3^2 + . . . + n^2 = (1/6)n(n+1)(2n+1)

Base case - First let us consider the base case where n=1. Then the left hand side of the equation becomes 1 and the right hand side is (1/6)12*3=6/6=1. Thus LHS=RHS and we are d...

Answered by Anna R. • Further Mathematics tutor

4922 Views

The velocity of a car at time, ts^-1, during the first 20 s of its journey, is given by v = kt + 0.03t^2, where k is a constant. When t = 20 the acceleration of the car is 1.3ms^-2, what is the value of k?

Our task is to find out the value of k, which we can determine from the equations for velocity or acceleration if we know 2 of the 3 variables in either equation. We are given the value of acceleration at...

Answered by Lascelle M. • Maths tutor

8094 Views