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Identify and explain 3 types of long-term memory - give an example of each.

Episodic – This is personal memory of information about events that we have experienced in our lives. This includes details of the time and place. For example remembering your first day ...

Answered by Chizara L. • Psychology tutor

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How is immunity reached after a vaccine is given? Include the roles of both T cells and B cells.

The vaccine contains either dead or attenuated pathogens, or they can contain just antigens from the pathogen. When one is injected with a vaccine the white blood cells within the body are able to recogni...

Answered by Chizara L. • Biology tutor

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Consider the unit hyperbola, whose equation is given by x^2 - y^2 = 1. We denote the origin, (0, 0) by O. Choose any point P on the curve, and label its reflection in the x axis P'. Show that the line OP and the tangent line to P' meet at a right angle.

We differentiate our equation with respect to x to find that 2x - 2y(dy/dx) = 0, and rearrange to find that dy/dx = x/y. We set P = (x, y). The slope of OP is given by y/x, and the slope of the tangent at...

Answered by Dylan C. • Maths tutor

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Show that the volume of the solid formed by the curve y=cos(x/2), as it is rotated 360° around the x-axis between x= π/4 and x=3π/4, is of the form π^2/a. Find the constant a.

After sketching a diagram of the curve and the solid for clarity, we see that we need to use the formula V = π∫ y² dx (with upper and lower bounds of 3π/4 and π/4 respectively) to calculate the...

Answered by Nicholas C. • Maths tutor

3378 Views

Describe how to perform a flame test to identify an unknown compound.

The equipment needed is a bunsen burner, a wire loop, some HCl, and the compound being tested (usually in powder form). Set up the bunsen burner so that it is on a blue flame. Take the wire loop and dip i...

Answered by Martha N. • Chemistry tutor

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