/// <summary>
 /// Shows an interstitial ad.
 /// </summary>
 /// <param name="ad">The interstitial ad returned from RequestInterstitialAd.</param>
 /// <see cref="OnOpened" />
 /// <see cref="OnClosed" />
 /// <see cref="OnExpiring" />
 /// <see cref="OnAudioStarted" />
 /// <see cref="OnAudioStopped" />
 public static void ShowAd(InterstitialAd ad)
 {
     if (IsInitialized())
     {
         SharedInstance.ShowAd(ad);
     }
 }
 /// <summary>
 /// Shows an interstitial ad.
 /// </summary>
 /// <param name="ad">The interstitial ad returned from RequestInterstitialAd.</param>
 /// <see cref="OnOpened" />
 /// <see cref="OnClosed" />
 /// <see cref="OnExpiring" />
 /// <see cref="OnAudioStarted" />
 /// <see cref="OnAudioStopped" />
 public static void ShowAd(InterstitialAd ad)
 {
     if (IsInitialized())
     {
         if (ad != null)
         {
             SharedInstance.ShowAd(ad);
         }
         else
         {
             Debug.LogError(Constants.AdsMessageErrorNullAd);
         }
     }
 }