Hi, why comments and latex \( do not work in the problem below? (As in the screenshot.)

##DESCRIPTION

## Total Probability

##ENDDESCRIPTION

##KEYWORDS('probability')

## DBsubject('Probability')

## DBchapter('ConditionalProbability')

## DBsection('Total Probability')

## Date('6/3/2002')

## Author('Saad Ghahramani')

## Institution('')

## TitleText1('Fundamentals of Probability')

## EditionText1('3')

## AuthorText1('Saad Ghahramani')

## Section1('3.3')

## Problem1('6')

########################################################################

DOCUMENT();

loadMacros(

"PGstandard.pl", # Standard macros for PG language

"MathObjects.pl",

"PGML.pl",

#"source.pl", # allows code to be displayed on certain sites.

#"PGcourse.pl", # Customization file for the course

);

# Print problem number and point value (weight) for the problem

TEXT(beginproblem());

# Show which answers are correct and which ones are incorrect

$showPartialCorrectAnswers = 1;

Context("Numeric");

#Context()->texStrings;

#BEGIN_TEXT

BEGIN_PGML

Let X, Y, and Z be random variables. Suppose that the variance of X is 0.7, Cov(X,Y) = 0.4, Cov(X,Z) = 1.2, and Cov(Y,Z) = 0.8. Find each of the following to two decimal places (if applicable).

(a)

\(Cov(2 Y, 3 X +1)\)

[____]{14.4}

# 4*9*0.4

(b)

Cov(2 X + Y, 3 X + 2 Z)

[____]{51.2}

# 4*9*0.7 + 4*4*1.2+ 9*0.4+ 4*0.8

END_PGML

#Context()->normalStrings;

ENDDOCUMENT();