Direct meas urement is __ measur ement obtained directly by means of me asuring ruments meas urement that depends on the skil l of the experimenter meas urement as a result of direct math ematical calculat ion

## Step 1<br />The problem is asking us to identify the correct definition of direct measurement. Direct measurement refers to the process of measuring a physical quantity directly using measuring instruments, without the need for any additional calculations or estimations.<br /><br />## Step 2<br />Let's analyze each option:<br /><br />1. "Measurement obtained directly by means of measuring instruments" - This option correctly defines direct measurement. It involves using measuring instruments to directly measure a physical quantity.<br /><br />2. "Measurement that depends on the skill of the experimenter" - This option does not define direct measurement. It seems to describe a subjective measurement, which is not the same as direct measurement.<br /><br />3. "Measurement as a result of direct mathematical calculation" - This option also does not define direct measurement. It seems to describe a calculated measurement, which is not the same as direct measurement.