The EL-W535TGB-BL model is perfect for students studying general math and science, pre-algebra, algebra, geometry, trigonometry, statistics, biology, and chemistry. This calculator performs 422 advanced scientific, math, and statistics functions. The EL-W535TGB-BL utilizes a 4-line display featuring an exponent symbol. WriteView display allows users to view their input and results as they would appear in a textbook. Includes a protective hard case and operates on twin-power (solar with battery backup). Power Source(s): Battery; Solar; Display Notation: Numeric; Number of Display Digits: 16; Display Characters x Display Lines: 16 x 4.