Experiments on subliminal perception commonly use an instrument to flash images too quickly for conscious recognition but slowly enough to be registered by the brain; this instrument is called a(n).

tachistoscope

Explanation:

Tachistoscope -

It is a type of instrument , which is capable to show an image for some specific time period , is referred to as tachistoscope .

It helps to show something at a higher speed .i.e. , to increase the recognition speed .

The main advantage of this instrument is to flash any image very quickly .

Hence , from the given information of the question ,

The correct answer is tachistoscope .

a progressive heart disease that affects pumping action of the heart muscles.

the answer is d

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