Solution: jQuery contains many features like CSS manipulation, AJAX, Effects, and animations, Utilities, HTML event methods, HTML/DOM manipulation. There are also jQuery plugins for every given task. jQuery simplifies complicated things in JavaScript.

Solution: The basic syntax of jQuery is $(selector).action(), $ sign defines access of jQuery, (selector) is HTML element, action() is for the jQuery action that is to be performed. E.g. $(“h1”).hide(), this will hide all the 
 elements.

Solution: In jQuery all the elments are selected by writing $(“*”). $(this) helps in selecting current HTML element. All the button elements are selected by writing $(“:button”). If we want to select a specific class we should write $(“.class_name”).

Solution: The actions that can be performed on the web page are called events. Some common DOM events are blur(), click(), bilnd(), change(), dbclick(), eroor(), delegate(), die(), event.data, event.currentTarget, event.pageX, mouseenter(), mousedown(), event.result, event.target, focus(), hover(), keydown(), focusout(), live(), load(), keyup() etc.

Solution: hover() method is the combination of mouseleave() and mouseenter(). It takes two functions. When the mouse leaves HTML element then mouseleave() function is called and when mouse enters HTML element then mouseenter() function is called.

Solution: jQuery has various fade methods including fadeout(), fadeTo(), fadeToggle(), fadeIn().
The syntax of fadeIn() is $(selector).fadeIn(speed,callback);
For fadeout() we use $(selector).fadeOut(speed,callback);
For fadeToggle we use $(slecetor).fadeToggle(speed,callback);
For fadeTo() syntax is $(selector).fadeTo(speed,opacity,callback).

Solution: jQuery have three slide methods namely slideUp(), slideDown() and slideToggle().
Syntax for slideDown() is $(selector).slideDown(speed,callback);
For slideUp() we use $(selector).slideUp(speed,callback).
For slideToggle() method the syntax is $(selector).slideToggle(speed,callback).

Solution: For attributes manipulation we use three methods named html(), text() and val(). The content of selected elements is returned by html(). The text content of selected elements is returned by text(). The values of form fields is returned by val().

Solution: In jQuery there are four methods to add new content namely prepend(), before(), after(), append(). The append() method inserts at the end, prepend() method inserts at the beginning of the content, after() method inserts the content after selected HTML element, befor() inserts before the selected HTML element.

Solution: There are several functions for CSS manipulation. Some of them are css(), removeClass(), toggleClass(), addClass(). The style attribute is returned by css() method. Classes are added by addClass() method. Classes are removed by removeClass() method. The toggling between adding and removing classes is achieved by toggleClass() method.