Approach 1: Using String for exposing elements

private final String METRIC_UNIT_TAB = "//a[.='Metric Units']";
private final String AGE_TXT = "cage";
private final String MALE_RAD = "csex1";
private final String HEIGHT_TEXT = "cheightmeter";
private final String WEIGHT_TEXT = "ckg";
private final String CALCULATE_BTN = "//input[@alt=\"Calculate\"]";
private final String RESULT_LBL = "bigtext";