The conversion of letters and numbers to code or symbols so that its contents cannot be viewed or understood is known as____________.

What is the rule for determining the number of significant figures to include in the product of a calculation that combines multiplication and subtraction?

A) Apply the rules for figure significance before and after every step involving subtraction. B) Complete the entire calculation and then round the final answer to have the same number of significant digits as the measurement with the most significant digits. C) Match the number of significant digits in the operations involving multiplication and division to those involving addition or subtraction after performing the calculation. D) Round each of the measurements in the calculation to have the same number of significant digits as the measurement with the least before beginning the calculation.

All of the following are thrombolytic drugs, except:

A) urokinase B) reteplase recombinant C) amylase D) anistreplase